Swivel seat for mechanical shovels



Nov. 10, 1959 c. J. DAVIS SWIVEL SEAT FOR MECHANICAL SHOVELS Filed April9, 1956 1 CHARLES J. DAVIS INVENTOR.

ATTO RN EY United States SWIVEL SEAT FOR MECHANICAL SHOVELS ApplicationApril 9, 1956, Serial No. 577,076

Claims. (Cl. 214131) This invention relates generally to seatconstructions, and pertains more particularly to a swivel seatespecially adapted for use in conjunction with mechanical shovels.

One important object of the invention is to provide a seat structurethat will rotate or pivot in unison with the boom on which themechanical shovel is mounted, thereby affording the operator anopportunity to watch and control properly the shovels movements withouthaving to turn in his seat to see the work being performed by theshovel.

Another object of the invention is to provide a seat structure of sturdyconstruction, yet one that will be quite comfortable under the ratherrigorous circumstances encountered in actual use. In this regard, it isan aim of the invention to incorporate into the structure a degree ofresiliency capable of minimizing the abrupt vibration or shock thatwould otherwise be transmitted at times to the operator from the shovelvia the boom. Another feature of the invention relating to comfort isthe provision of appropriate foot rests, such a feature lending itselfvery readily to incorporation into the more basic seat structure formingthe subject matter of the present invention.

A further object of the invention is to provide a seat structure of theforegoing character that will be of simple design and yet at the sametime serve its intended purpose Without interfering with partsconstituting the boom actuating mechanism. More specifically, it isplanned that the boom actuating mechanism be adjustable to swing theboom from a center position through 90 to either side at the selectionof the operator, and the invention contemplates that the operators gazebe automatically directed to either of these selected side positions asWell as a more central one. v To accomplish this, provision is made forrotating the seat structure with ample clearance so as to avoidobstruction with other parts, as mentioned above.

The invention, together with other objects attending its production,will be more clearly understood when the following description is readin connection with the accompanying drawings, in which:

Figure 1 is a perspective view of the seat structure as it appears inactual use, a tractor for supplying suitable fluid power to the boomactuating mechanism being depicted in phantom outline;

Figure 2 is a fragmentary perspective view with the chair unit removedso as to illustrate to better advantage the chair mounting platform thatwould otherwise be partially concealed; and

Figure 3 is a plan view of the combination pictured in Figure l, theView additionally including the mechanical shovel in one of two extremeside positions that it may assume with the other side position beingindicated in phantom outline.

Referring in detail to the drawing, the invention is exemplified inassociation with a tractor indicated generally by the numeral 10, thetractor being equipped with a hydraulic pressure system from which boomactuating power can be obtained via appropriate control valves Q i r APatented Nov. 10, 19 59 The frame 14 includes a pair of vertical studs16, 18 connected by transverse members 20, 22. While not important to anunderstanding of the instant invention, the studs 16, 18 are ofrectangular cross-section into which are telescopically received legelements 24, 26, these legs being vertically adjustable in an individualmanner so as to maintain said frame level when employed on roughterrain.

The frame 14 has projecting therefrom in cantilever fashion a pair ofrelatively short beams 28, 30, the upper beam 28 being fixedly securedto the transverse member 20, and the lower beam being welded orotherwise rigidly secured to the transverse frame member 22.

The function of the vertically spaced beams 28, 30 is to journaltherebetween a swivel post 32. A lower clevis element 34 pivotallyanchors the lower end of a boom 36 which in turn has suspended therefroma mechanical shovel 38 (Figure 3). The boom 36 may be raised and loweredby means of a hydraulic cylinder 40, this hydraulic cylinder beingpivotally anchored to the swivel post 32 bya clevis 42. I

The operators seat structure'and spring mounting therefore whichconstitute my invention include the seat proper, designated as a wholeby the numeral 44, two spaced generally horizontal spring steel seatsupporting platforms 54, and a rigid upright metal pedestal 46 supportedby the swivel post 32, and which in turn supports the platforms 54.

1 The seal proper may be of any desired type. The'seat illustratedincludes spaced upright panels 64 which serve as supporting side legs, aback 62, and a panel supported seat bottom 60.

The upright pedestal 46 is of channel cross section with a portion ofthe web being removed at its upper end to provide the flanges 50 withfree upper ends, these ends preferably being rounded to fit the matingends of the platforms 54. The lower ends of pedestal flanges 50 aresecurely welded to the spaced forwardly projecting arms of the clevis42, as shown.

The forward end of each seat supporting platform 54 is offset bent to ageneral 2 cross section configuration, the bend radius beingsubstantially the same as the radius of curvature of the upper ends of,the pedestal flanges 56.

-'I'he offset bent forward ends of the platform springs 54 arecomplementally fitted against and welded to the curved upper ends offlanges 50 with the major portions of the platforms projectingrearwardly in a substantially horizontal common plane to clear the upperend of frame 14 as the swivel post 32 is rotated, as clearly shown inFig. 2. It will be-noted that the platforms 54 are sep arated from eachother, and that each is of suflicient width as theproject laterallyoutward from that flange of the pedestal to which it is welded. Theabovedescribed mounting provides a cantilever support for the platforms 54,thus greatly increasing their ability to absorb shocks transmitted fromthe swivel post through the pedestal 46.

To complete the structure, the spaced side legs 64 of seat 44 are weldedor otherwise suitably secured to the respective platform springs 54along fore and aft disposed lines 66, leaving a portion of each platformexposed outside each respective side of the seat to serve as foot restsfor the shovel operator.

Since the mechanism for oscillating the swivel post 32 to swing the boom36 from side to side is not a part of this invention, it is not believednecessary to describe its construction and operation.

From the above description it will be understood, however, that as theswivel post is rotated in either direction about its axis the operatorsseat 44 is necessarily moved through the same are, and seat 44 is alwaysin a position facing the boom. Platform springs 54 constitute a shockabsorbing support for the seat 44 of the operator, and thereby minimizeoperator fatigue. The springs are so arranged and independentlysupported so that each may absorb a shock load independent of the other,and so that they cooperate to support the shifting weight of theoperator, regardless of which spring may necessarily support the greaterportion of such weight.

It will be apparent from the drawings and from the above descriptionthat the applicant has provided a novel cantilever seat structure for amechanical shovel which is distinguished by a pedestal 46 connected toone side of the shovel swivel post and which extends upwardly beyond anysurrounding frame structure together with a cantilever support 54 whichis connected to the pedestal at its forward end and which rearwardlyoverhangs the frame structure 14 for unimpeded movement of the assemblyfrom side to side about the post axis. The seat 44 is connected to thecantilever support at a region rearwardly of the connection to thepedestal in order to provide cantilevered springing of the seat.Moreover, the pedestal is of relatively narrow cross section as shown sothat it may be swung with the swivel post through'a maximum angle on theorder of 180 without any interference with the frame 14. 7

With regard to the specific rearward oifset of the frame of the seatwith respect to the pivot axis, it will be apparent from the drawingthat the seat is so arranged that the pivot axis of the swivel post,when extended upwardly, intersects the region occupied by the body ofthe operator when seated on said seat. For convenience, the extendedaxis of the swivel post 32 is identified in Fig. 1 as 32a. It will beapparent to one skilled in the art upon inspection of the drawing thatthe invention contemplates that the swivel post 32 and pedestal 50 berigid with one another forming, for structural purposes, an integralunit.

Having described the invention with sufficient clarity to enable thosefamiliar with this art to construct and use it, I claim:

1. In a mechanical shovel of the class wherein a rigid upright framejournals the upper and lower ends of an upright boom swinging swivelpost the axis of which lies outside the plane of the frame, a shockabsorbing seat structure for the shovel operator comprising: a rigidupright pedestal carried rigidly by said swivel post on that side of thepost which is normally remote from the shovel frame, said pedestalprojecting upward to a level above the top of the shovel frame; a pairof spaced elongated platform type steel springs arranged side by side ina common horizontal plane, each having an end rigidly secured to theupper end of said pedestal, the remaining otherwise unsupported portionsof said springs projecting toward and overlying the upper end of theshovel frame, said springs being capable of independent flexing movementwith respect to the pedestal; and an operators seat spanning the spacebetween said springs, the two sides of said seat being secured to therespective upper surfaces of said springs with the seat facing towardthe pedestal.

2. The seat stlucture described in claim 1 in which the springs are ofsuch lateral dimensions that a portion of each spring projects laterallyfrom its respective side of the seat to provide foot rest surfaces forthe operator.

3. The seat structure described in claim 1 in which the pedestal is ofchannel cross section with a portion of the upper end of the web beingremoved to provide the flanges thereof with laterally spaced free upperends, and in which those ends of the springs which are attached to thepedestal are rigidly welded to the respective free upper ends of thepedestal flanges.

4. A seat assembly for a mechanical shovel comprising, in combination; avertical generally planar supporting frame, a swivel post journaled insaid frame for move ment about a vertical axis, an upright pedestalrigidly connected to the swivel post and extending upwardly along oneside thereof, means including a rearwardly extending cantilever supportin the form of a substantially fiat spring lying in a horizontal plane,the forward end of the cantilever support being secured to the upper endof the pedestal, an operators seat having a frame and facing toward saidpedestal, the frame of said seat being secured to said cantileversupport at a region spaced rearwardly from the forward end of thesupport for cantilevered springing of said seat, said pedestal havingsufiicient height so that it extends upwardly clear of said frame withthe cantilever support rearwardly overhanging said frame, said swivelpost being spaced outwardly from the plane of the frame and saidpedestal having a relatively narrow cross section for unrestrictedlateral swinging movement of said seat, support and associated swivelpost through an angle of substantially 5. In a seat construction for amechanical shovel, the combination comprising, a vertical generallyplanar supporting frame, a vertical swivel post journaled in said frame,a boom secured to said swivel post, said swivel post being so mountedthat its axis is offset forwardly from said frame so that said boom isfree to swing substantially 180 from a right hand position in which itlies flatly adjacent said frame to a left hand position in which it liesflatly adjacent said frame in the opposite direction, a verticalpedestal on said swivel post, a seat assembly on said pedestal, saidseat assembly having a seat portion which extends rearwardly andlaterally from the swivel post axis and arranged with respect to theswivel post axis so that the axis extends through the space occupied bythe body of the operator when seated thereon, said seat assembly furtherhaving a foot supporting portion positioned to be engaged by and tosupport the feet of the operator when seated on said seat, said pedestalbeing extended upwardly from said frame so that the seat assemblyincluding the foot-supporting portion thereof is upraised clear of theupper edge of said frame so that the boom may swing through its entirerange of swinging movement free of interference between said seatassembly and said frame and with the operator maintained at all timesfacing said boom.

References Cited in the file of this patent UNITED STATES PATENTS1,932,241 Brown Oct. 24, 1933 2,418,299 Gorsuch Apr. 1, 1947 2,452,280Zahller Oct. 26, 1948 2,478,082 Brown Aug. 2, 1949 2,678,140 Goetz May11, 1954 2,712,849 Exton July 12, 1955 2,772,720 Zody et al. Dec. 4,1956 2,792,138 Olson May 14, 1957 FOREIGN PATENTS 1,046,255 France July8, 1953

